Hi there, I'm not sure the best way about this so I thought it ask on here. I have a project which reads 4 analogue sensors which outputs 0-5v. Currently this works great, but I'd like to make each sensor wireless ( independently of each other) I've been doing some research, but I've never read on how to read from more than one wireless device to a single arduino board. Ideally I'd like to have 4 transmitters all sending info back to a single receiver connected to an arduino. The sensors will only need to transmit a max of 10 meters. What are my options to get this done?Thanks on advance for your thoughts.

PeterH

Functionally, the nRF24L01+ radio transceivers are just what you need.

They're tiny little cards that can be wired directly to any Arduino and take almost no power. Each instrument would consist of a minimal Arduino and the radio transceiver, plus power supply. The low power also translates to low range. I'm not sure the cheap non-amplified versions would stretch to 30' under ideal conditions, and if there are any obstructions I'd say that was out of the question. There is an amplified version with increased range but I have no experience of them.

If you take this approach and find you're running out of range, you have the option of installing additional units to act as relays.

Yes you need the Arduino, an Wireless SD shield or an XBee shield. These to shields then need the XBees or WiFly modules added. WiFly have the same footprint as the XBees and give you WiFi.

However for a range of 30ft a wire connection should be ok. (Use twisted pair).

If you go the XBee route, you can connect the sensor directly to the XBee - no Arduino required. That requires a bit of configuration magic to get working, and requires using API mode to get the data on the coordinator.

If you go the XBee route, Rub Faludi's "Building Wireless Sensor Networks" is a worthwhile investment.

Paul, I've ordered a copy of that book, looking forward to a read. So with the xbee I can have one arduino with xbee module, and have 4 sensors, each with there own xbee module to talk the the xbee module attached to the single arduino?

Sound perfect. Do you know of anything online I can read up on this before my book arrives?

tack

I've had nRF24L01+ow power modules transmitting about 30ft through a couple of walls and a floor. In open space I think they'd work fine.

For about £1.30 each from China, it's certainly affordable to get yourself a few and give them a go with the Maniacbig libraries. RF24Network was designed as a sensor network so should do exactly what you have in price.

If you do need longer range then the high power version of nRF24L01+ is available for about £7.50. I've had them doing about 150m through a window and down a street in an urban environment. If you can get height to clear the Fresnel Zone better then I'm sure you could increase that.

With RF24Network you can insert repeater nodes to extend range, in a similar topology to XBee but at a fraction of the price.

Thanks, sounds like these nRF24L01+ may also be an option. I have had a quick read up on them Nd I love the price. If I wanted my arduino board to read 4 analogue inputs, would I need 5 or 8 of the nRF24L01+ boards?